Abstract 4104: Organization of Atrial Signals is Critical Prior to Cardioversion of Atrial Fibrillation with Intravenous Flecainide: Insight from Spectral Analysis of Intracardiac Electrograms

Introduction & Hypothesis: Studies in catheter ablation of atrial fibrillation (AF) show that an increase in cycle length (CL) and higher organization index (OI) is associated with termination of AF. We hypothesize that similar changes can be seen in chemical cardioversion with Flecainide Methods: Patients who were still in AF at the end of catheter ablation for AF were given intravenous flecainide. OI and dominant frequency (DF) were obtained by Fast Fourier Transform of coronary sinus electrograms over 10s in AF, before and after flecainide infusion. Mean CL was also calculated. Results: 28 patients were identified (18 paroxysmal AF and 10 persistent AF). 8 cardioverted to sinus rhythm (SR) with flecainide. In all patients, mean CL increased from 211 ± 44 ms to 321 ± 85 ms (p <0.001). Mean DF decreased from 5.2 ± 1.03 Hz to 3.6 ± 1.04 Hz (p <0.001). Mean OI was 0.33 ± 0.13 before and 0.32 ± 0.11 after flecainide (p = 0.90). Comparing patients who cardioverted to SR with those who did not, OI post-flecainide was 0.41 ± 0.12 vs 0.29 ± 0.10 (p=0.013) and relative change in OI was 29 ± 33% vs −3.9 ± 27% (p=0.016) respectively. No significant difference was noted in the change in CL and DF in the 2 groups. Logistic regression showed that a greater relative increase in OI (p=0.04), a higher OI post-flecainide (p=0.03) and SR at start of procedure (p=0.03) are independently associated with cardioversion to SR with flecainide. Conclusion: Increase in OI, independent of changes to the CL and DF, appears critical to AF termination with flecainide. The increase in OI may reflect an increase in size and reduction in the number of re-entrant circuits, which together with slowing of atrial activation, result in return to SR.

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Clinical Outcomes of Computational Virtual Mapping-Guided Catheter Ablation in Patients With Persistent Atrial Fibrillation: A Multicenter Prospective Randomized Clinical Trial

Frontiers in Cardiovascular Medicine ◽

10.3389/fcvm.2021.772665 ◽

2021 ◽

Vol 8 ◽

Author(s):

Yong-Soo Baek ◽

Oh-Seok Kwon ◽

Byounghyun Lim ◽

Song-Yi Yang ◽

Je-Wook Park ◽

...

Keyword(s):

Atrial Fibrillation ◽

Clinical Trial ◽

Catheter Ablation ◽

Computational Modeling ◽

Controlled Trial ◽

Dominant Frequency ◽

Complication Rates ◽

Clinical Recurrence ◽

Significant Difference

Background: Clinical recurrence after atrial fibrillation catheter ablation (AFCA) still remains high in patients with persistent AF (PeAF). We investigated whether an extra-pulmonary vein (PV) ablation targeting the dominant frequency (DF) extracted from electroanatomical map–integrated AF computational modeling improves the AFCA rhythm outcome in patients with PeAF.Methods: In this open-label, randomized, multi-center, controlled trial, 170 patients with PeAF were randomized at a 1:1 ratio to the computational modeling-guided virtual DF (V-DF) ablation and empirical PV isolation (E-PVI) groups. We generated a virtual dominant frequency (DF) map based on the atrial substrate map obtained during the clinical AF ablation procedure using computational modeling. This simulation was possible within the time of the PVI procedure. V-DF group underwent extra-PV V-DF ablation in addition to PVI, but DF information was not notified to the operators from the core lab in the E-PVI group.Results: After a mean follow-up period of 16.3 ± 5.3 months, the clinical recurrence rate was significantly lower in the V-DF than with E-PVI group (P = 0.018, log-rank). Recurrences appearing as atrial tachycardias (P = 0.145) and the cardioversion rates (P = 0.362) did not significantly differ between the groups. At the final follow-up, sinus rhythm was maintained without any AADs in 74.7% in the V-DF group and 48.2% in the E-PVI group (P < 0.001). No significant difference was found in the major complication rates (P = 0.489) or total procedure time (P = 0.513) between the groups. The V-DF ablation was independently associated with a reduced AF recurrence after AFCA [hazard ratio: 0.51 (95% confidence interval: 0.30–0.88); P = 0.016].Conclusions: The computational modeling-guided V-DF ablation improved the rhythm outcome of AFCA in patients with PeAF.Clinical Trial Registration: Clinical Research Information Service, CRIS identifier: KCT0003613.

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Kolmogorov Complexity of Coronary Sinus Atrial Electrograms before Ablation Predicts Termination of Atrial Fibrillation after Pulmonary Vein Isolation

Entropy ◽

10.3390/e21100970 ◽

2019 ◽

Vol 21 (10) ◽

pp. 970 ◽

Cited By ~ 1

Author(s):

Stępień ◽

Kuklik ◽

Żebrowski ◽

Sanders ◽

Derejko ◽

...

Keyword(s):

Atrial Fibrillation ◽

Catheter Ablation ◽

Pulmonary Vein ◽

Pulmonary Vein Isolation ◽

Coronary Sinus ◽

Kolmogorov Complexity ◽

Similarity Index ◽

Dominant Frequency ◽

Significant Difference ◽

The Rich

Atrial fibrillation (AF) is related to a very complex local electrical activity reflected in the rich morphology of intracardiac electrograms. The link between electrogram complexity and efficacy of the catheter ablation is unclear. We test the hypothesis that the Kolmogorov complexity of a single atrial bipolar electrogram recorded during AF within the coronary sinus (CS) at the beginning of the catheter ablation may predict AF termination directly after pulmonary vein isolation (PVI). The study population consisted of 26 patients for whom 30 s baseline electrograms were recorded. In all cases PVI was performed. If AF persisted after PVI, ablation was extended beyond PVs. Kolmogorov complexity estimated by Lempel–Ziv complexity and the block decomposition method was calculated and compared with other measures: Shannon entropy, AF cycle length, dominant frequency, regularity, organization index, electrogram fractionation, sample entropy and wave morphology similarity index. A 5 s window length was chosen as optimal in calculations. There was a significant difference in Kolmogorov complexity between patients with AF termination directly after PVI compared to patients undergoing additional ablation (p < 0.01). No such difference was seen for remaining complexity parameters. Kolmogorov complexity of CS electrograms measured at baseline before PVI can predict self-termination of AF directly after PVI.

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Abstract 17454: The Effect of Catheter Ablation on Coronary Sinus Cycle Length in Persistent Atrial Fibrillation

Circulation ◽

10.1161/circ.142.suppl_3.17454 ◽

2020 ◽

Vol 142 (Suppl_3) ◽

Author(s):

Ghaith Zaatari ◽

Jorge Bohorquez ◽

Raul Mitrani ◽

Jason Ng ◽

Justin Ng ◽

...

Keyword(s):

Atrial Fibrillation ◽

Catheter Ablation ◽

Coronary Sinus ◽

Cycle Length ◽

Persistent Atrial Fibrillation ◽

Posterior Wall ◽

Quality Signals ◽

Before And After ◽

Ventricular Activation ◽

Ablation Success

Background: While pulmonary vein isolation (PVI) for treatment of persistent atrial fibrillation (PeAF) is successful in approximately 50%, acute termination of PeAF is rarely observed. Prolongation of cycle length (CL) by 10% is often utilized as an indicator of successful catheter ablation (CA). Objective: To evaluate coronary sinus (CS) cycle length (CL) before and after CA for PeAF. Methods: CA for PeAF was performed in 31 patients (24males, age 63±9 yrs, CHA2DS2-VASc 2.3±1.7, LVEF 49±10%) with PVI, with 4 (13%) also having posterior wall isolation. A multielectrode catheter was placed in the CS and maintained throughout the procedure. CS electrograms were recorded for 10 seconds prior to CA and after completion of CA. No patient reverted to sinus rhythm during CA. CS CL was determined using customized software for activation detection and verified visually, excluding ventricular activation and low quality signals (n=3). The shortest CL among the recording electrodes was used for analysis. Results: CS CL pre- and post-CA were 182.4±23.0 and 191.6± 29.9 ms (p= 0.04) with change from baseline of 5.4±12.7%. The figure shows the histogram for change in CS CL from baseline. Only 7/28 (25%) of patients had CS CL prolongation >10%. Of ten patients who were free of AF off anti-arrhythmic drugs at 1 year, CS CL increased 4.0±6.1%; 2/10 had CS CL prolongation >10%. Of 6 patients with recurrent AF, CS CL increased 13.8±20.7%; 4/6 had CS CL prolongation >10%. Conclusion: Our data demonstrate that CS CL prolongation >10% is not a useful marker of outcomes in patients undergoing catheter ablation for PeAF. This highlights the need to identify other indicators of acute ablation success.

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Regions of Highly Recurrent Electrogram Morphology at Sites of Low Cycle Length Accurately Reflect Arrhythmogenic Substrate for Atrial Fibrillation – Implications For a New, Mechanism Guided Therapeutic Approach for Atrial Fibrillation

10.1101/2020.12.10.419754 ◽

2020 ◽

Author(s):

Shin Yoo ◽

Markus Rottmann ◽

Jason Ng ◽

David Johnson ◽

Bassel Shanab ◽

...

Keyword(s):

Atrial Fibrillation ◽

Cycle Length ◽

Dominant Frequency ◽

Nerve Fibers ◽

Atrial Pacing ◽

Parasympathetic Innervation ◽

Complexity Measures ◽

Parasympathetic Nerve ◽

Arrhythmogenic Substrate ◽

Before And After

ABSTRACTBackgroundAlthough atrial electrograms (EGMs) are thought to reflect pathophysiological substrate for atrial fibrillation (AF), it is not known which electrograms are suitable targets during AF ablation. We hypothesized that electrogram morphology recurrence (EMR) better reflects arrhythmogenic AF substrate than traditional frequency and complexity measures of AF. In a canine rapid atrial pacing (RAP) model of AF, we assessed the relationship between EMR and traditional AF electrogram measures, rotational activity in the atria, fibrosis, myofiber orientation and parasympathetic innervation.MethodsPersistent AF was induced in 13 dogs by RAP for 6-8 weeks. High-density epicardial mapping (117 electrodes) was performed in six atrial sub-regions. EMR measures Recurrence percentage (Rec%) and cycle length of the most frequent electrogram morphology (CLR), Fractionated Interval (FI), Organization Index (OI), Dominant Frequency (DF) and Shannon’s Entropy (ShEn) were analyzed before and after atropine administration. Myocyte fiber orientation, amount of fibrosis and spatial distribution of parasympathetic nerve fibers were quantified.ResultsRec% was greatest in the appendages, and CLR was lowest in the posterior left atrium. Rec%/CLR correlated with FI, OI and the complexity measure ShEn, but not with DF. All electrogram measures were poorly correlated with fibrosis and myofiber anisotropy. Rec% correlated closely with stability of rotational activity. Unlike other measures, Rec% correlated closely with spatial heterogeneity of parasympathetic nerve fibers; this was reflected in CLR response to atropine.ConclusionEMR correlates closely with stability of rotational activity and with the pattern of atrial parasympathetic innervation. CLR may therefore be a viable therapeutic target in persistent AF.

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Prolongation of atrial fibrillation cycle length during catheter ablation at sites of maximal dominant frequency

Heart Rhythm ◽

10.1016/j.hrthm.2005.02.998 ◽

2005 ◽

Vol 2 (5) ◽

pp. S316-S317

Author(s):

Prashanthan Sanders ◽

Omer Berenfeld ◽

Yoshihide Takahashi ◽

Ravi Vaidyanathan ◽

Mélèze Hocini ◽

...

Keyword(s):

Atrial Fibrillation ◽

Catheter Ablation ◽

Cycle Length ◽

Dominant Frequency

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Abstract 10199: Right Atrial Fibrillation in Humans - Evidence for A Right Atrial Driver Activated by Right Atrial Ectopies

Circulation ◽

10.1161/circ.132.suppl_3.10199 ◽

2015 ◽

Vol 132 (suppl_3) ◽

Author(s):

Hideyuki Hasebe ◽

Kentaro Yoshida ◽

Masataka Iida ◽

Naoki Hatano ◽

Toshiro Muramatsu ◽

...

Keyword(s):

Atrial Fibrillation ◽

Spectral Analysis ◽

Family History ◽

Catheter Ablation ◽

Left Atrial ◽

Volume Ratio ◽

Dominant Frequency ◽

Right Atrial ◽

History Of ◽

Atrial Ectopy

Background: A left-to-right dominant frequency (DF) gradient exists in acute atrial fibrillation (AF) in animals and in paroxysmal AF (PAF) in humans. PAF initiated by right atrial ectopy (PAF-RAE) is rare. Adenosine triphosphate (ATP) can be effective to unmask such a rare non-pulmonary vein (PV) ectopy and accelerate the frequency of a reentrant source of AF (driver). Objective: This study aimed to investigate characteristics of patients with PAF-RAE using pharmacological maneuvers and spectral analysis. Methods: Enrolled were 111 consecutive patients referred for catheter ablation of lone PAF. Infusions of isoproterenol and ATP were used to induce AF. Patients with PAF initiated only by PV ectopies and with PAF-RAE were classified into the PV-ectopy group (N=32) and RA-ectopy group (N=6), respectively. ATP was also injected during ongoing AF to unmask the AF driver. High RA, coronary sinus (CS), and PV-left atrial junction (PV-LAJ) electrograms underwent spectral analyses. Results: RA-ectopy group patients were younger (49±13 vs. 63±7 years, p<0.001), more commonly had a family history of AF (67% vs. 9%, p<0.001), and had a higher RA appendage/RA volume ratio (0.22±0.022 vs. 0.15±0.055, p=0.002) than PV-ectopygroup patients. The most common origin of RA ectopy was the base of the RA appendage (67%). There was a baseline right-to-left DF gradient in the RA-ectopy group (PV-LAJ: 6.0±0.4, CS: 5.7±0.7, RA: 7.4±0.8 Hz, p<0.05), in contrast to a left-to-right DF gradient in the PV-ectopy group (PV-LAJ: 5.9±0.8, CS: 5.3±0.7, RA: 5.2±0.8 Hz, p<0.01). ATP injection mainly increased the DF of the high RA, augmenting a right-to-left DF gradient in the RA ectopy group (PV-LAJ: 8.0±2.0, CS: 7.8±1.0, RA: 10.7±0.7 Hz, p<0.05), whereas it augmented a left-to-right DF gradient in the PV-ectopy group (PV-LAJ: 7.9±1.0, CS: 6.4±0.5, RA: 6.6±1.2 Hz, p<0.05). Conclusions: PAF-RAE may be maintained by a reentrant driver localized in the RA (so-called right atrial fibrillation).

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Letter by Platonov et al Regarding Article, “Dominant Frequency of Atrial Fibrillation Correlates Poorly With Atrial Fibrillation Cycle Length”

Circulation Arrhythmia and Electrophysiology ◽

10.1161/circep.110.943274 ◽

2010 ◽

Vol 3 (2) ◽

Cited By ~ 3

Author(s):

Pyotr G. Platonov ◽

Martin Stridh ◽

Leif Sörnmo

Keyword(s):

Atrial Fibrillation ◽

Cycle Length ◽

Dominant Frequency

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Evaluation of the Renin-Angiotensin-Aldosterone system before and after catheter ablation of atrial fibrillation

Heart Rhythm ◽

10.1016/j.hrthm.2005.02.752 ◽

2005 ◽

Vol 2 (5) ◽

pp. S240

Author(s):

Frédéric Sacher ◽

Agnes Georges ◽

Prashantan Sanders ◽

Jean-Benoit Corcuff ◽

Philippe Schraub ◽

...

Keyword(s):

Atrial Fibrillation ◽

Catheter Ablation ◽

Renin Angiotensin Aldosterone System ◽

Renin Angiotensin ◽

Before And After

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The Association of Pre-Existing Left Atrial Fibrosis with Clinical Variables in Patients Referred for Catheter Ablation of Atrial Fibrillation

Clinical Medicine Insights Cardiology ◽

10.4137/cmc.s15036 ◽

2014 ◽

Vol 8s1 ◽

pp. CMC.S15036 ◽

Cited By ~ 7

Author(s):

Jane Dewire ◽

Irfan M. Khurram ◽

Farhad Pashakhanloo ◽

David Spragg ◽

Joseph E. Marine ◽

...

Keyword(s):

Atrial Fibrillation ◽

Catheter Ablation ◽

Left Atrial ◽

Af Ablation ◽

Group 4 ◽

Significant Difference ◽

History Of ◽

Group 2 ◽

Magnetic Resonance Imaging Mri ◽

Left Atrial Fibrosis

Introduction Atrial fibrillation (AF) recurrence after ablation is associated with left atrial (LA) fibrosis on late gadolinium enhanced (LGE) magnetic resonance imaging (MRI). We sought to determine pre-ablation, clinical characteristics that associate with the extent of LA fibrosis in patients undergoing catheter ablation for AF. Methods and Results Consecutive patients presenting for catheter ablation of AF were enrolled and underwent LGE-MRI prior to initial AF ablation. The extent of fibrosis as a percentage of total LA myocardium was calculated in all patients prior to ablation. The cohort was divided into quartiles based on the percentage of fibrosis. Of 60 patients enrolled in the cohort, 13 had <5% fibrosis (Group 1), 15 had 5-7% fibrosis (Group 2), 17 had 8-13% fibrosis (Group 3), and 15 had 14-36% fibrosis (Group 4). The extent of LA fibrosis was positively associated with time in continuous AF, and the presence of persistent or longstanding persistent AF. However, no statistically significant difference was observed in the presence of comorbid conditions, age, BMI, LA volume, or family history of AF among the four groups. After adjusting for diabetes and hypertension in a multivariable linear regression model, paroxysmal AF remained independently and negatively associated with the extent of fibrosis (-4.0 ± 1.8, P = 0.034). Conclusion The extent of LA fibrosis in patients undergoing AF ablation is associated with AF type and time in continuous AF. Our results suggest that the presence and duration of AF are primary determinants of increased atrial LGE.

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